1. Field of the Invention
The present invention relates to a method for measuring the dimension or clearance of a gap of a carrying path including a magnetic head through which a card is passed when a passenger sets the card on an automatic ticket checking and collecting machine at a train station or in an one-man control bus, or on other similar machine. The present invention covers a reading unit of credit cards and prepaid cards. Further, the invention also relates to a gap clearance measuring laminated member and a gap clearance measuring system directly used for implementing the foregoing method.
2. Description of Related Art
An automatic ticket examining (or checking and collecting) machine at a train station or in a bus, a telephone adapted for telephone cards, or a reading device of credit cards or prepaid cards reads the information stored in a magnetic card or writes new data to the card by passing it between a carrying roller and a magnetic head. It is necessary to properly control the contact pressure of the magnetic head with respect to the card so as to enable the magnetic head to perform accurate reading and writing.
For cards other than magnetic cards, it is required to control the gap relative to a reading head to a proper dimension i.e. gap clearance. For this purpose, it is necessary to precisely adjust the gap formed between the magnetic head or the reading head and the carrying roller facing against the magnetic head or the reading head in accordance with the predetermined thickness of a card which passes therethrough. In order to adjust the gap clearance, conventionally, the machine has been disassembled and a thickness gauge has been applied or the card has been repeatedly passed through the gap until the gap is properly adjusted.
The aforesaid conventional method in which the card is repeatedly passed through the gap to achieve proper adjustment of the gap has been posing a problem in that it takes much effort and time.
Especially in the case of the automatic ticket examining machines with an extremely high operation frequency, maintenance staff must check them every morning, and the problem described above has been serious because of the need of much time and effort, that is, low efficiency. In addition, there has been another problem in that the gap adjustment depends on the experiences and intuition of each maintenance person, so that the adjusted gap tends to be nonuniform or inaccurate.
The present invention has been made with a view toward solving the problems described above, and it is a first object thereof to provide a method for measuring a gap dimension which method permits easy, accurate measurement of the gap through which cards are passed and also permits the adjustment of the gap to be performed objectively and accurately without depending on the experiences or intuition of the maintenance staff. It is a second object of the present invention to provide a laminated member for measuring a gap dimension, the laminated member being used directly for implementing the foregoing method. Further, it is a third object of the present invention to provide a system for measuring a gap dimension, the system being used directly for implementing the foregoing method.
The first object of the present invention is attained by a provision of a method for measuring the dimension of a gap for passing a card therethrough, comprising the steps of:
(a) providing a laminated member comprising a pressure measuring film superposed on an elastic mat, the pressure measuring film causing a pressurized portion thereof to develop a color, the elastic mat being formed such that the thickness thereof gradually increases from a front end of the mat to a rear end of the mat along the direction in which the card is inserted into the gap;
(b) passing said laminated member through said gap; and
(c) inspecting the position where the pressure measuring film starts to develop the color to determine the dimension of said gap.
The elastic mat employed for the method may be, for example, the one having its thickness varying in steps. Preferably, the elastic mat is provided with a plurality of projecting sections or rows, which are parallel to the card inserting direction and which are arranged in stripes, at least on one surface thereof so that it may be easily compressed and deformed. The top surfaces of the projecting sections should be formed in steps.
Alternatively, the elastic mat may be formed so that it has a uniform thickness and the pressure required for causing a predetermined compression and deformation gradually decreased in the direction in which cards are inserted. As another alternative, a plurality of laminated members comprised of pressure measuring films superposed on a plurality of elastic mats which are uniform in thickness but different from each other in thickness are prepared, then the laminated members are passed through the gap in order, starting with a thinnest one, for example, so as to find the dimension of the gap from the thickness of the one that starts to develop a color.
The second object of the present invention is attained by a provision of a laminated member for measuring the dimension of a gap for passing a card therethrough, comprising:
an elastic mat having the top surface provided with a stepped portion that gradually grows taller in steps from a front end thereof to a rear end thereof; and
a pressure measuring film superposed on said elastic mat and causing a pressurized portion thereof to develop a color.
Preferably, at least one surface of the elastic mat is provided with a plurality of projecting rows which are parallel to the direction in which cards are inserted, and steps are formed on the top surfaces of the projecting rows.
The first object of the present invention is also attained by a provision of a method for measuring the dimension of a gap for passing a card therethrough, comprising the steps of:
(a) providing a laminated member comprising a pressure measuring board and an elastic mat, the pressure measuring board having plural pressure sensors arranged substantially in the direction in which the card is inserted into the gap to electrically detect the pressure applied in the direction of the thickness of the respective pressure sensors, the elastic mat being superposed to cover at least said pressure sensors, the thickness of the elastic mat increasing from a front end of the mat to a rear end of the mat along the direction in which the card is inserted into the gap;
(b) passing said laminated member through said gap;
(c) storing the pressures detected by said plural pressure sensors; and
(d) after the passage of said card through said gap, reading the stored pressures from the laminated member to determine the dimension of said gap.
The elastic mat used for this purpose may be formed so that the thickness thereof changes in steps toward the leading edge thereof or it may alternatively be formed to have a surface inclining continuously. The data on the pressures detected by the respective pressure sensors when the laminated member is passed through the gap is temporarily stored in the memory provided on the pressure measuring board, and the contents of the memory are transferred via a wiring cable to an external host computer after the passage through the gap, then the pressure distribution can be analyzed by the external host computer. The data on the pressures detected when the laminated member passes through the gap can be read by a reader provided in the carrying path by wireless via an antenna, and it- can be further transferred to the external host computer from the reader.
The second object of the present invention can be attained also by a laminated member for measuring the dimension of a gap for passing a card therethrough, comprising:
an elastic mat having a stepped portion which gradually grows higher in steps from the front end thereof to the rear end thereof; and
a pressure measuring board placed on said elastic mat and having plural pressure sensors arranged along said stepped portion.
The elastic mat may be provided with a continuous slope instead of the stepped portion. The pressure sensors may be load cells employing strain gauges or carrier diffusion type semiconductor pressure sensors. Two sheets, in which many parallel thin-wire electrodes formed on one surface of each of insulating sheets are covered with a thin film of pressure-sensitive resistive ink, are prepared and placed together face to face in such a manner that the electrodes are opposed to each other so that the electrodes of each sheet intersect at substantially right angles in order to provide the intersections of the electrodes as the pressure sensors. In this case, many pressure sensors can be arranged in a matrix pattern to permit two-dimensional pressure distribution.
The pressure measuring board has a microcomputer, a semiconductor memory, and an external connection terminal to store the pressure data in the semiconductor memory when the laminated member passes through the gap and to make connection to the external host computer via the external connection terminal so as to transfer the data to the external host computer after the laminated member passes through the gap. The data may be transferred by wireless. For instance, the laminated member may be equipped with a single-chip computer and an antenna to transfer data to and from the antenna of the reader provided in the card carrying path. In this case, the single-chip computer incorporates a processor for processing the outputs of the pressure sensors, a modulator, a transmitter, and a receiver.
A plate or foil type battery may be employed for the power supply of the microcomputer, the semiconductor memory, the single-chip computer, etc. of the laminated member. In this case, the laminated member may be provided with a switch so that the switch may be manually turned ON immediately before the laminated member is inserted in the carrying path or the switch may be automatically turned ON by the pressure applied by the carrying rollers or the like during the travel through the carrying path. Alternatively, a magnetic field may be formed in the card carrying path and the magnetic induction electromotive force generated when the laminated member is passed through the magnetic field is utilized to charge a capacitor and the electric charges accumulated in the capacitor may be employed for the power supply.
The third object of the present invention is achieved by a system for measuring the dimension of a gap for passing a card therethrough, comprising:
a laminated member which is passed through a path for said card, comprising an elastic mat having a stepped portion that gradually grows higher in steps from the front edge toward the rear edge thereof, a pressure measuring board that is placed on said elastic mat and has plural pressure sensors arranged along said steps, a single-chip computer incorporating a processor for processing the outputs of said pressure sensors, a modulator, a transmitter, a receiver, and an antenna;
a reader provided in the carrying path of said card to transmit and receive data and information to and from said laminated member by wireless, said reader comprising an external antenna, a transmitter, a receiver, a demodulator, and a microcomputer which processes the output of said demodulator and transmits and receives information to and from an external host computer; and
the external host computer which is connected to said reader and that determines the distribution of received pressures according to received data to determine the dimension of said gap.
When the laminated member passes through the gap, an impact is applied to a point of the slope or stepped portion of the elastic mat at which the height is matched to the dimension or clearance of the gap. After that, the portion of the slope or stepped portion higher than that point is subjected to the pressure that gradually increases as the laminated member moves on and that is applied in the direction of the thickness of the laminated member.
Accordingly, the pressure change between the pressure detected by the pressure sensor located under the point (of the slope or the stepped portion) to which the impact was applied first and the pressure detected by the pressure sensor located under the point from which the height gradually increases among many pressure sensors on the pressure measuring board increases. The pressure change is processed by the processor and the result is stored in the memory before it is transferred to the external host computer later. Alternatively, the pressure change detected by the pressure sensors may be transmitted to the reader installed at the carrying path by wireless via the antenna, then transferred to the external host computer from the reader.
Based on the read data, the external host computer obtains the distribution of the pressures applied to the pressure measuring board when the laminated member passed through the gap so as to determine the dimension of the gap from the obtained pressure distribution. Analyzing changes in the direction of the card width or time-dependent changes of the pressure distribution observed when the laminated member goes through the gap makes it possible to determine whether the carrying path has been set properly, including how much the laminated member swings laterally during the passage.